Leukemia, or cancer of the white blood cells, is the most common type of childhood cancer. Scientists at this center are examining how early exposure to toxic chemicals might contribute to leukemia in children.

Research at this center focuses on the effects of pesticides, tobacco-related contaminants, polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs, or brominated flame retardants) in the womb and early in life. To determine if and how, early exposure to such chemicals might cause childhood leukemia, scientists are trying to identify which chemicals are associated with a higher risk for leukemia and are looking at how these chemicals interact with genes known to be involved in leukemia development.

Researchers at this children’s center are evaluating environmental exposures in the womb and in early childhood, using existing home dust samples and biospecimens from the Northern California Childhood Leukemia Study. They are also examining environmental and genetic influences for distinct leukemia subtypes and sharing their findings with other researchers and the public to help prevent childhood leukemia and improve children's health.

Project 1: Childhood Leukemia International Consortium Studies
The chemicals that children are exposed to can have a dramatic impact on their health and the interaction between various chemicals they are exposed to can change that reaction in many ways. Some studies have linked tobacco smoke and pesticides applied in homes with childhood leukemia; however, most of these studies are limited by small sample sizes. This project pools data from 14 case-control studies in 10 countries within the Childhood Leukemia International Consortium (CLIC) to provide a more definitive assessment of the contribution of environmental chemicals to childhood leukemia. The researchers are examining linkages between parental smoking and home pesticide use, genetic variations that make children more or less likely to be able to process foreign chemicals and the risks of different types of childhood leukemia in different populations.

Project 2: Exposure Assessment for Childhood Leukemia
This project aims to improve scientists’ ability to assess whether – and when – children have been exposed to environmental chemicals and to identify which chemicals raise the risk for childhood leukemia. The study builds on data from the Northern California Childhood Leukemia Study using blood samples from 250 childhood leukemia patients. The researchers are looking to see if there is an association between levels of nicotine, PAHs (polycyclic aromatic hydrocarbons from combustion), PCBs (polychlorinated biphenyls), and PBDEs (polybrominated diphenyl ethers – flame retardants) in the blood and measurements of chemicals in house dust. Using methods newly developed by UC Berkeley, investigators analyze newborn dried blood spots (DBS) collected at birth to quantify internal doses of chemical exposures.

Project 3: Prenatal Exposures, DNA Methylation, and Childhood Leukemia
Once researchers identify a link between a chemical exposure and childhood leukemia, the next step is to find out how the chemical causes cancer. The cause often involves changes in a person’s genetic code or the activation or repression of certain genes. This project examines how certain toxins affect a person’s cells at the molecular level to help advance methods for early detection of leukemia diagnosis using newborn DBS from the general population.

The center is partnering with the Children’s Environmental Health Network, a national organization that specializes in outreach, education, and advocacy on children’s environmental health, and the UCSF Pediatric Environmental Health Specialty Unit, which reaches persons concerned about their childrens’ health and the pediatric health care community. These organizations are both key elements of the overall network supporting advances in children’s environmental health across the country.

The communities for research communication and community outreach for this Center include:

The national community of those interested in advancing children’s environmental health;

The national community of pediatric health care professionals with an interest in environmental health issues;

The national community of persons interested in leukemia;

The California community of persons interested in childhood leukemia.

The Center is also involving the cooperative network of the Pediatric Environmental Health Specialty Unit (PEHSU) system and partners such as the American Academy of Pediatrics and non-profits in developing and disseminating informational materials. Center investigators are also reaching out to organizations including foundations that work with those interested and involved with leukemia, such as the Lymphoma and Leukemia Society.